Airport fueling system



Aug. l, 1944- A. J. IGRANBERG 2,354,915

I I AIRPORT FUELING' SYSTEM Filed March 4, 1942 JNVENToR. AL @ser J Gam/afm atented Aug. 1, 1944 UNITED STATES PATENT OFFICE AIRPORT FUELING SYSTEM K Albert J Granberg, EmeryyillaCalif. Application March 4, 1942, 'serial 10.433399 (o1. s-s) 7 Claims.

My invention relates to airport fueling systems and more particularly to an airport fueling system which is ideally adaptedfor use in time of War. The system maintains the main storage supply of gasoline orother fuel under safe conditions where it is incapable of flooding the eld as might be the case With full pressure systems which are usually dependent on an outside water supply for delivery pressure. This supply may at anytime be subject to failure in case of attack.

I `Amongthe objects of my invention are: To provide an airport fueling system having maximum safety; to provide an airport fueling system in whichfthe main lfuel supply is never under pressure; to provide an airport fueling system wherein means are .provided for compensating for varying delivery rates; to provide an airport fueling system that can vbe electrically operated either Vfrom .public service power mains, or from a local auxiliary power supply; to provide an airport fueling system having a main supply maintained at atmospheric pressure, with a small auxiliary supply .maintained under pressure for emergency use; to provide 4anVV airport .fueling supply embodying a vpump and pump bypass, together with means under normal circumstances for utilizing the pump without the use of the bypass; to provide -an airport fueling system wherein a small amount of emergency fuel is maintained under air .pressure with means to prevent air being absorbed by the fuel While under pressure, and to provide a simple, safe and efficient fuel supply for airports,` designed to withstand attack. l

. My invention possesses numerous other objects and features of advantage, some of which, together with the foregoing, will be set forth in the following description ofV specific apparatus embodying vand utilizing my novel method. It is therefore to be understood that my method is app licable to other apparatus, and that I do not limit myself, in any way, -to the apparatus ofthe presentapplication, vas I `may adopt various otherr apparatus embodiments, `utilizing the method,

within thelscopeof theappended claims.

In the drawing: y Fig. .1 .is a top plan viewof one preferred form of my'invention, with the portions of the apparatus normally above the [ground shown in solidV manyV airport fueling systems in use today,l the Amain"fuel supplyV tank `c ln'itainir'ig for ex-v ample, highly inflammable fuel such as airplane gasoline of high octane rating, fis placed under water pressure from the local water supply Amains with Ygasoline outlets led tp Ifuel pits ollsland outlets for example, scattered over the field.' case of attack for example, or bombingattack `of theairfielithese systems are subject to two distinct failures. The first .fai-lure may be due to loss of pressurerink the Water supply mains by breakage thereof, and thus no fuel can be delivered to the fuel outlets. ,Howeven another and more `serious objection can be raised to such s ystems in that bombs may open thefuel pit outlets while the water :pressure 4 is still on lthe f 'main tank, thus leading to flooding of the field with large quantities of fuel Vand ignition thereof. Furthermore, when Vmain storage tanks vare placed under Water pressure, filling vof these tanks after they are empty is slow, ,as the water must be discharged therefrom. As thetankslare being filled the system becomes inoperative. Y

My present invention includes a fueling ysystem, wherein the main storage .tank or tanks can be deeply buried and -mantained'at atmospheric pressure, so that they may be lled any time without interfering with the operation of the fueling system. A pump is utilized .to remove the fuel from .the main storage by suction. I am aware that suction pumps have been utilized to take fuel from main storage tanks before, but they have not provedsatisfoctojry for airport .use because of the `varying demandimposed .upon the pump due to the fact that none ..o`r.,all of .the fuel outlets may be in use at one time. Under such conditions, .the pump has to ,be designed .to be able to supply `all of the fuelopit outlets. When only one of the outlets is rbeing utilized, it has been customary heretofore to utilize a pump bypass to return the excess outlet fuel to the pump inlet. Under these conditions, however, `fuel pumps heat up and high-test gasoline .for example, becomes hot and introduces gasoline vapor into the pipes. In general sucha system vis' not satisfactoryexcept when a substantiallyconstant demand is being made upon the pump,

In' my present invention the .only use Yof such a bypass .is as a. safety feature incase of failure of other `features of my invention nlater to be .described. Furthermore, .my invention .contemplates the maintenance of a relatively small amount of fuel, under air pressure in a separate" tank with the fuel however, being separated from the air by Aa water column to prevent absorption of air by the fuel, inasmuch .as it has been found A that, hightes t gasoline forexample, will'absorb up to 25% of air when the two are placed in oontact under pressure. A certain amount of fuel is therefore maintained as an auxiliary supply in all cases so that in spite of pump failure, this auxiliary supply is always available for use. Furthermore, the amount held in the auxiliary supply is suciently small, so that even if the fuel pit outlets were to be opened by bombing, for example, the amount of fuel liberated will not be sufficient to cause a serious conagration. Under these circumstances I am able to utilize the air pressure against the auxiliary fuel supply as a buffer and lter 'for absorbing changes in demand on the system, and also utilize the variation of air pressure due to the change in demand, to control the operation f the pump so that the pump need only operate in accordance with the demand as reflected upon the auxiliary supply.

Other safety features are provided so that there will be maximum opportunity for the system to remain in operation under attack. Even though the system be damaged by attack,the system is so protected that the main fuel supply is prevented from ilooding'the `fleld'and the auxiliary fuelv supplyis sufciently small to conne any conilagration as a'result of the escape thereof to aminorpe'ril. d l l My invention indeta'il maybe more fully understood by direct reference to the drawing.

A main fuel tank I may be buried in the ground tof'any desired depth. If desired this main fuel storage tank may Atake the' form'of a number of separateinterconnected tanks. In any event a filling Vstern 2 is provided extending to the surface ofthe ground which may also be utilized as a gauge stem.V A vent 3 is also provided. A suctionY outlet 4 is provided, first passingr through a check-valve or foot-valve 5 into an inlet pipe 6 ofample size connectedr to'a positive displacement pump I preferably positioned above the ground for proper-servica'driven by a motor 8. This motor 8 may be, for example, under normal conditions operated by thejlocal power supply mains and as is quite customary at airports, a local 'auxiliary lpower supply may be utilized for motor I-87' with" automatic switch-'over if desired along with-the-fother electrical appurtenancesv of the airport so thatthere will be no interruption in motor'service in case of attack and failure of themainslf' rn, j vv`vThe pumpl is preferably provided with a bypass `of any conventional' type which iscapable of operating at 'predeterminedpressure indicated by the numeral 9. j i l The pump discharge is connected by means of pipe I0 4through a hand valve'II to an auxiliary tank I2, `this auxiliary tank being preferably buried in the'ground and connected at the bottom thereof by vconnecting Vpipe I4, to a, second auxiliarytank I5 also buried beneath the ground. Tanks I2 and I5 are" preferably of substantially the same cubicalv content, and are preferably placed beneath the ground with their bottoms on thesarne plane. f

Outletpipe I0 al'sdconnects through a` main outlet valve I' I j'to a' eld pipe line I8 preferably passing beneath the ground to various i-leld outlets as may befexemplie'd by a tank loading stern I5, island outlets 20 for example, having a capanty of 25 gallons veach or'mo're, and4 a plurality, of fuel 'pit outlets 2| having for example a capacity of 35 to 100 gallons each.v

' 'Iheftop of tank I5 is provided with a water fill stem 25 andan upwardly extending air pipe 26, the latter branching above ground to pass in one kdirection through a check-valve 2l, a hand valve 28, to a hand operated air-injector 29. The other branch of air pipe 26 passes to a pressure gauge 3D, also to a safety valve 3I and to an air pressure operated switch 32, connected to the electric current supply as indicated above. Pressure switch 32 is set to close at, for example, 25 pounds pressure, and open at 60 pounds. The circuit under the control of pressure-operated switch 32 passes through a motor Starter 35, and then through wires 36 to motor 8.

Auxiliary tanks I2 and I5 are preferably of about 300 gallons capacity and are capable of withstanding 100 pounds pressure. Each of these tanks is preferably filled about half full of water. Tank I5 is preferably provided with an upper float-valve 3l controlling the outlet of the tank into pipe 26, and also a second float valve 38 at the bottom thereof controlling the inlet from pipe I4. Both of these float-valves are indicated diagrammatically in dotted lines. Top float-valve 31 is arranged so that it will close if thewater level should by accident or otherwise reach the top of the tank, and the bottom valve 3,8 is arranged so that this valve will close should the water level become too low at the bottoniY ofthe tank. The water in the tanks serves as a means of separating the fuel in tank I2 from the air in tank I5, and the fuel in tank I2 is preventedy from ever entering tank I 5.

In operation, after the tanks I2 and I5 have been filled with water as described, the manually operated air injector 29 is operated until the hand on the pressure gauge 3D shows the minimum pressure required to operate the'pressure switch 32. The system is now ready to'perform and the current from the mains or other supply may be connected. The pump then starts, dueto the action of the pressure switch, and the pump will continue to transfer fuel from the main storage tank I to the auxiliary storage tank I2, and will at the same time deliver fuel out to the field lines if any are open. Should any of the field lines be in service and should they take the full capacity of the pump, the pump will continue to operate until some of the lines are shut off. Under these conditions the excess fuel will then ll tank I2, push-v ing the Water from tank I2 into tank I5 through connection I4 until the pressure gauge indicatesl the maximum pressure desired in tank I5, in which case the pressure switch 32 will shut off the pump. Should some of the fuel lines still be operating they will continue to obtain fuel by delivery from tank I2 until the pressure in tankA I5 reaches the minimum value at which time the pressure switch 32 will again start the pump, and repeats 'the performance. Thus, under normal conditions no fuel will be bypassed by pump I inasmuch as the bypass 9wil1 be adjusted to operate only at pressures above those normally encountered -in the normal operation of the system.

The numerous safety devices described above have an important bearing on the operation ofthe system. jFor example, the safety ,valve 3I only' for operation whenV and' if throughA misunder standing or otherwise, the air injectorl 29 is operated when unnecessary, or is operated solong as to raise the pressure in the tank I5 to too high a value. The float-valve?! at the vtop of tank'l5v will operate only if pressure switch 32 f ails toV shut off the pump after the pressure in tank I5 has" reached its preset maximum. Under these con-u ditions, outlet pipe 26` will'be closed to passage of liquid and excess pressureA will be set up upon pump 'I. Only under these conditions will the bypass operate, and the systemv will still'op'erate as a' straight-y punp bypass systemuntil the pressure y'switch 32 has been serviced. Float-valve -38 at the bottom Aof the tank -I -willonlyjoperate if the power line should fail or be deliberately -disconnected. If such is the caseand a fuel outlet Ais lstill dispensing, the pressure in tankf will vlower the water levelin tank Ia'nd therebyfforcewater -int'o tankv I2, forcing fuel `from tank I2 into-the fuel-outletat the outlying station'uiftil'the Wat-'er levelin--tank I5 reaches float-valve 38. This' floatvalve will then close and willnot permitanymore water to be discharged. No more fuel can bedelivered. Thusthereis;at all times in tank I2=an amountlof -fuelavailable'for ruse as long as pres-l sure'. remains in tank'l5, `even though theremainderof the system isdisruptedr However, the .amountfof1fuel-he1d inftank 'I 2, which may be for example under maximum pressure about 200 gallons, is not sufficient to cause an extensive conflagaration in case the system fails and one or more of the fuel outlets on the eld are rendered open by attack, or for that matter by accident. Thus, the system is fully protected against accident, and is also protected against forcing the entire contents of the main storage tanks onto the field in case of open fuel outlets. `Even though the tank I is so injured as to break it open and make it available for a conflagratiom the re will be confined to the neighborhood of the buried tanks only, and obviously the main storage tank may be placed at some outlying location Where such a re could not be dangerous to other structures.

If desired, there is one other contingency that may be taken into account from a safety point of view. It is the possibility that one or more of the field outlets I9, or 2I may be bombed open while the current supply to motor 8 is still intact. Under many circumstances, of course, there will be opportunity for operators of the airport to cut off the current supply to the pump in case of attack. However, the possibility might occur that the current supply could not be cut off. If, under there conditions, one or more of the eld outlets I9, 2l) and 2l were bombed open then the motor and pump might operate to force fuel from tank I onto the eld through the open outlets until the main storage tank I was emptied. This would, of course, flood the field and might cause a conflagration.

In case it is desired to avoid such a possibility, protection can be obtained by providing a continuously energized circuit 4I) having series loops 4I extending to a position adjacent each outlet I0, 2l] and ZI. This circuit may follow the entire extent of the outlet piping of the pump 8 including, for example loops over tanks I2 and I5. The current in circuit 40 may be utilized to hold a relay 42 closed, to connect the main current supply to switch 32. Upon failure of current to pass through any part of circuit 40, relay 42 will open and prevent current from the current supply reaching switch 32.

Under these conditions, if any of the outlets I9, 20 or 2|, or any part of the pump outlet piping, is bombed sufficiently to open either the outlets or the pipe, the circuit 40 will be opened at the same time, thus automatically cutting off current to motor 8 and preventing any further operation of the pump 1. The maximum amount of fuel that can then be forced onto the eld is the amount held under pressure in tank I2. If, in individual installations it is felt that even this amount of fuel is too much to be released upon the field, a pressure release solenoid valve 43 can be utilized as indicated in Fig. 2, to open safeandmetnod c'fjdispensingjthefuer but Whitt;k

also maintainns the "fuel rvin main .storageI 'tanks "at atmosphericfpressure,fso vthat Ytlley can b'e 'illj vd Y at'anytime; v'Atthe' Sametime the system main-1l tains a small auxiliary amoun't'of vfu'el'available incase of lcorriple'te failure o'fpower supply;

I claim:

1. In an airport fueling system which includes a main fuel supply tank, a pump for taking fuel from said tank by suction, field o utlets supplied by said pump, and a motor driving said pump; a pair of auxiliary tanks connected together adjacent the bottom thereof, each of said tanks having an amount of water therein, a connection from the top of one of said auxiliary tanks to" the outlet of said pump, means for maintaining air under pressure over the water in the other auxiliary tank, and electrical means for controlling said motor in accordance with the pressure of said air.

2. In an airport fueling system which includes a main fuel supply tank, a pump for taking fuel from said tank by suction,eld outlets supplied by said pump, and a motor driving said pump; a pair of auxiliary tanks connected together ad# jacent the bottom thereof, each of said tanks having an amount of Water therein, a connection from the top of one of said auxiliary tanks to the outlet of said pump, an air pipe connected to the top of said other auxiliary tank, means for maintaining air under pressure over the water in said latter tank, and a pressure switch operated by pressure in said air pipe and connected to control said motor.

3. In an airport fueling system which includes a main fuel supply tank, a pump for taking fuel from said tank by suction, eld outlets,supplied by said pump, and a motor driving said pump; a pair of auxiliary tanks connected together ad# jacent the bottom thereof, each of said tanks having an amount of water therein, a connection from the top of one of said auxiliary tanks to the outlet of said pump, an air pipe connected to the top of said other auxiliary tank, means for injecting air into said air pipe to a predetermined pressure, and a pressure switch operated by pressure in said ai!` pipe and connected to control said motor.

4. In an airport fueling system which includes a main fuel supply tank, a pump for taking fuel from said tank by suction, field outlets supplied by said pump, and a motor driving said pump; a pair of auxiliary tanks connected together adjacent the bottom thereof,each of said tanks having an amounts of water therein, a connection from the top of one of said auxiliary tanks to the outlet of said pump, an air pipe connected to the top of said other auxiliary tank, means for maintaining air under pressure over the water in said latter tank, a pressure switch operated by pressure in said air pipe and connected to control said motor, and means for preventing water from entering said air pipe.

5. In an airport fueling system which includes a main fuelv supply tank,a pump for taking fuel from said tank by suction, eld outlets supplied by said pump, anda motor driving said pump; a pair of auxiliarytanks connected together adjacent the bottom thereof, each of saidrtanks havingV 4an amount of water therein, a connection from the Atop of one.v of said auxiliary tanks to the outlet of saidv pump, an air pipe connected to the top of said other auxiliarytank, means for maintaining air under pressure over the water in lsaid latter tank, a' pressure switch operated by pressure in said` air pipe and`connected to control saidmotor, means for preventing water from entering said air pipe, and means for preventing air 15 from passing fromVone/tank to -said bottom connection.. l 6'. Apparatus inaccordance with claim 1 wherethe other through in a normally iclosed electrical circuit follows the pump supply lines to said field outlets, and means operable by interruption of Ysaid circuit for deenerg'izingrvsaid motor, and for releasing the air DICSSUIQ over Said Water.

l Il. An vairport fueling system comprising a fuel supply tank; a eld outlet for said system having fuel connection with said tank; a lmotordriven pump insaid connection` forvpumping fuel from s aid'tank tosaid field outlet; means responsive to pressure in said system on the discharge side of said pump for determining normal operating periods, of said pump motor and pump; and an electric circuitA controlling .the flow of operating energy tg said pump motor subject to.said pressureresponsive meanss aid electric circuit being disposed alongfsaid fueiconnection to said outlet.

.ALBERT J. GRANBERG. 

